Microsoft revealed an update on its progress on the Hot Reload capabilities that will ship with Visual Studio 2022. Hot Reload allows a developer to edit code and apply those changes immediately in an already running application, without needing to restart that application to see those changes.
Currently Hot Reload is available as a preview in Visual Studio 2019, but the company expects the full experience to ship with Visual Studio 2022 when it reaches general availability in a few weeks.
Hot Reload will work with most app frameworks, according to Microsoft. This includes typical app types such as Console, Windows Forms (WinForms), WPF, UWP, WinUI 3* and most types of ASP.NET web projects (for code-behind edits) including ASP.NET MVC, Web API, and even older Web Forms projects.
Microsoft’s goal with Hot Reload is to save developers as many app restarts between edits as possible, making them more productive by reducing the time spent waiting for apps to rebuild, restart, re-navigate to the previous location where they were in the app itself.
Hot Reload is also available without the debugger when targeting most of .NET 6 apps. “This feature is exclusive to .NET 6+ and those apps not targeting .NET 6 (.NET 5 or below) will not support the “no debugger” scenario and must use the debugger to get access to Hot Reload functionality,” Dmitry Lyalin, principal program manager for .NET (Hot Reload, XAML Tooling & .NET MAUI) explained in a blog post.
Developers who are able to use both Visual Studio 2022 and work on apps that target .NET 6 will get the benefits of the most polished and capable Hot Reload experience and developers targeting .NET 6 will continue to get more improvements in future Visual Studio 2022 updates, according to Microsoft.
However, Xamarin.Forms apps won’t support .NET Hot Reload in iOS and Android scenarios and apps built using F# or those targeting .NET Native will not support Hot Reload.
The new UI includes improvements such as a Visual Studio session-wide option to Rebuild and Apply Changes on each Hot Reload rude edit. Also, it includes a rebuild and apply your code changes command that can be accomplished with a single click, instead of multiple manual steps.